Intronic microRNA-directed regulation of mitochondrial reactive oxygen species enhances plant stress tolerance in Arabidopsis
Intronic microRNA-directed regulation of mitochondrial reactive oxygen species enhances plant stress tolerance in Arabidopsis
复制标题
DOI：
10.1111/nph.19168
复制
发表时间：
2023-08-07
期刊：
影响因子：
9.4
通讯作者：
Yan，Kang
中科院分区：
文献类型：
--
作者：
Xu，Wei-Bo;Zhao，Lei;Yan，Kang
MicroRNAs(MiRNAs)在调节植物发育和逆境反应中起着至关重要的作用。然而，内含子miRNAs在植物中的功能和机制还不是很清楚。本研究报道了一种内含子miR400产生的胁迫响应RNA剪接机制，miR400通过下调其目标表达来调节活性氧物种(ROS)的积累并提高植物的耐受性。为了监测内含子剪接事件，我们使用了依赖内含子剪接的荧光素酶转基因系。高浓度镉处理后，由于含有miR400的内含子被保留，抑制了成熟miR400的产生，导致荧光素酶活性下降。此外，我们还证明了在Cd处理下，miR400的靶标五肽重复蛋白1(PPR1)通过诱导ROS的积累而起到正向调节作用。Ppr1突变影响了电子传输链中的复合体III的活性和线粒体基因cMB的RNA编辑。本研究阐明了内含子剪接是内含子miR400产生的关键步骤，并强调了内含子miRNAs在提高植物抗逆性方面的‘信号转导’功能。
MicroRNAs (miRNAs) play crucial roles in regulating plant development and stress responses. However, the functions and mechanism of intronic miRNAs in plants are poorly understood.This study reports a stress‐responsive RNA splicing mechanism for intronic miR400 production, whereby miR400 modulates reactive oxygen species (ROS) accumulation and improves plant tolerance by downregulating its target expression.To monitor the intron splicing events, we used an intronic miR400 splicing‐dependent luciferase transgenic line. Luciferase activity was observed to decrease after high cadmium concentration treatment due to the retention of the miR400‐containing intron, which inhibited the production of mature miR400. Furthermore, we demonstrated that under Cd treatments,Pentatricopeptide Repeat Protein 1(PPR1), the target of miR400, acts as a positive regulator by inducing ROS accumulation.Ppr1mutation affected the Complex III activity in the electron transport chain and RNA editing of the mitochondrial geneccmB.This study illustrates intron splicing as a key step in intronic miR400 production and highlights the function of intronic miRNAs as a ‘signal transducer’ in enhancing plant stress tolerance.